Hi @martin23, it looks like you are reading a value from outside your loop within your loop. Seeing you are splitting your data in batches of 1, your “Airtable1” node will only ever see one item at a time. The expression {{ $node.Airtable.json.id }} which your “Airtable1” uses will therefore read the first item from your “Airtable” node whenever it runs.
The easiest way to solve this would be to get rid of the loop like so:
This way, both your “Airtable” and your “Airtable1” nodes will see the exact same items they run and the update succeeds:
If you do want to use the loop, consider using an expression of {{ $('Airtable').item.json.id }} instead. $(“<node-name>”).item will fetch the corresponding item from a previous node, even if the number or order of items has changed between nodes.